Come a Knocking

My engien is knocking how can I tell if it is a lifter type head problem or a cilender type block problem. I have a saturn sc2 with 1.9 l DOHC

Lifters tap under the valve cover. Crankshaft or connecting rod bearings knock way down low in the block.

Where is the noise coming from?

How old is the car and how many miles?

1998 157000

It seems to be coming form the top but that could be wishful thinking. I let the oil run low (stupid I knew that there was an oil leak just forgot to check the oil) and it started knocking and when I put filled the oil the knocking got quieter but did not go away. I then changed the oil but that did not help any more than just filling the oil did.

Can I use the hose stethoscope method for listening for the knock? I am at work so I cant do it until I get home.

When the oil was “low”, how much did you have to add to get it up to where the level was between the add and full marks on the dipstick?

If the answer is 4 or 5 quarts you likely know the answer is going to be bad. You could be knocking at the top and bottom of the motor. You can’t do much more to hurt it now so you might as well keep driving it.

At the same time start looking for either another car, or a salvage yard motor would be a good idea.

3 put it in the middle

Yes you can use a hose or a long screwdriver.

If three quarts only put it up to the middle there wasn’t much oil in there. I fear the worst.

If it is coming from the head and I don’t hear much form the block. what are my chances of having a used head fix the problem?

How long will the engine last if I just drive on it. I commute abut 50-60 mi round trip per day.

For this answer you’ll need an experienced mechanic to hear the noise and identify the source. If it is a rod bearing(s) they can deteriorate pretty fast, and throw a rod. Valve noise might last a long time, just get noisier. Main bearings, hard to say.

The low oil might have sludged up the oil passages to the valves and that would be your best bet for getting some more life from the motor.

thank you you have bean a real help.